The present invention relates in general to an intra-oral control unit and system and, in particular it relates to an intra-oral control unit and system for use in controlling the environment of persons having less than full use of their limbs and which is especially useful for quadriplegics.
An increasing number of patients with high-level spinal cord injuries resulting in quadriplegia are being treated. The quadriplegic condition can result from many causes such as trauma which is due to vehicular and diving accidents, gunshot wounds, etc., spinal tumors or congenital malformations of the vertebrae, bacterial and viral infections, and neuromuscular disorders such as muscular dystrophy and multiple sclerosis. Many quadriplegic patients have a serious problem in communication during the early phase of their hospital stay. This problem with communication is a result of being ventilator-dependent, or of having minimal voice control. The treatment of the quadriplegic patient is first concerned with the survival of the patient and this usually occurs in an intensive care unit. At this stage of treatment, the patient has either significantly compromised respiratory parameters or is mute due to ventilator dependence. Many such patients have no mobility of the head due to traction. Many patients with cervical lesions remain in permanent traction for four to six weeks during which time the head is held in a position perpendicular to the surface of the bed. Because of this degree of restriction and the isolation in an intensive care unit, it is vital that the patient be provided with a device to gain the attention of the clinician.
Many types of patient-operated call systems have been used for such patients and are described in the literature. Such call devices may generally be categorized as sip/puff mechanisms, mouth wands and physiological response devices such as eye blink detectors and movement activated switches. All of these devices suffer from disadvantages associated with their use. The use of an air activated switch, such as a sip/puff device, is often not possible due to significantly compromised respiratory parameters or ventilator dependence. Even when sufficient air supply exists, the patient's speech may tend to be unreliable in volume and pronunciation. Thus, voice actuated devices are also unreliable. While the use of a mouth wand or stick is feasible, its communicative properties are slow and tiring to the user. Physiological response devices, such as eye blink detectors and movement activated switches tend to be unreliable. Physiological response devices falling into this category, in addition to eye blink detectors, include devices for the detection of head or shoulder motions, devices for the detection of myoelectric signals from the muscles around the head and neck, devices for the detection of eyebrow motion, jaw or chin movement and tongue contact. Utilization of such devices including those dependent upon residual arm, shoulder or leg movement of the patient for activation of physiological response devices is undesirable because such TJU-16 devices tend to produce inconsistent results and must be customized to each patient.
The present invention seeks to overcome the afore-mentioned disadvantages by providing a call device which capitalizes upon the fact that one voluntary function which is usually intact in a quadriplegic patient is the lingual function. Since the control of the tongue is vital for the primary acts of swallowing and eating, its capability is always evaluated early in the patient's treatment and reinforced if necessary. Devices for environmental control by a quadriplegic utilizing the tongue are known. One such system has been described for use by a quadriplegic which includes the placement of an electrical contact below the external lower lip which is activated by the tongue of a quadriplegic in order to sound an alarm. See M. E. Tunstall and M. P. Bolten, "Simple Alarm for Quadriplegic Patients", Vol. 32, Anesthesia, pages 177-178, 1977. Such a device suffers from severe disadvantages.
After the initial therapeutic phase in an intensive care unit, the quadriplegic patient has usually progressed to the point where in addition to the need for calling someone, it is desirable to control surrounding devices. Devices are known which control various pieces of equipment used by quadriplegics such as alarms, wheelchairs, computers, telephones and typewriters. In this category, devices are known which utilize head movements, sip/puff switches, vocal commands and finger or thumb movements for the activation of environmental control units. Such techniques suffer from the disadvantages referred to above.
It is an object of the present invention to provide an environmental control unit and system which obviates the aforementioned disadvantages.
It is a further object of the present invention to provide an environmental control unit and system which may be used as a call device and which alternatively may also be used to control external equipment and appliances.
It is a still further object of the present invention to provide such a unit and system which is activated by the tongue but which is mounted internally.
It is still another object of the present invention to provide an environmental control system capable of monitoring a plurality of quadriplegic patients simultaneously.
It is a still further object of the present invention to provide a system which is useful in any application in which an individual is required to control his external environment but is unable to use his limbs.